Friction stream feeder



July 14, 1942.

T. J. KAUFFELD FRICTION STREAM FEEDER Filed Sept. 16, 1941 ZSheets-Sheo 1 July 14,1942.

' T. .1. KAUFFELD 2,289,502

FRICTION STREAM FEEDER Filed Sept. 16. 1941 2 Sheets-Sheet 2 I y I -i 1/ Patented July 141, 1942 20 Claims.

This invention relates to devices for the successive feeding of fiat sheets of paper or other material from a pile or bank in which they are stacked, to a point of delivery, at which point certain operations may be performed on the sheets. Such feeding devices are applicable to the feeding of paper sheets to printing presses, folding, cutting or slitting machines, and many devices.

More particularly the invention relates to sheet feeders of the type commonly known as stream feeders, which are adapted to forward successive sheets of material in overlapping arrangement, means being provided for initiating the separating and feeding of a succeeding sheet from the pile well before the rear edge of the next preceding one has moved beyond the front edge of the pile.

This mode of advancing sheets has found favor, especially in the printing industry, on ac- Count of the extreme rapidity of feeding at tained and theconsequent saving of time; and much ingenuity has been exercised and numerous proposals have been made for accomplishing these results. employed suction cup members for seizing and separating the sheets and for moving them forwardly off the pile. Others have used vertically reciprocating suction. gripping members for seizing the top sheet and lifting its rear portion off of the pile, and a mechanical element such as a reciprocating hook for catching the rear edge of the sheet and pushing it forwardly. However, difficulties have been encountered in the successful practical adaptation of these latter P devices in the matter of damaged sheets, the feeding of doubles, and the inability to accurately and effectively feed sheets of thin, light weight material.

It is the general object of the present invention to provide a novel and improved sheet feeder of the stream feeding type, which is of simple and compact construct-ion, easy and economical to manufacture, operate and maintain, and which will eiliciently handle sheets of widely (hffering widths, thicknesses, and textures. A more particular object is to provide a stream feeder in which a frictional sheet contactin member is employed, 1. 6., which. is automatically actuated to periodically rub against the successive top sheets of the pile a forward direction to move them relatively to the sheets next below in order to separate them from the pile and present them to the Many of these prior devices have a feeding member rarest DitIQE forwarding conveyor usually provided in advance of the front side of the pile.

The present invention has the same general objects as that described in my copending application, Serial No. 411,086, filed of even date herewith, but provides certain additional features which facilitate the feeding of certain kinds of sheets.

In addition to' the main fore and aft friction buckling member, there is provided by this invention additional frictional devices for buckling the rear corners of the uppermost sheets diagonally inwardly and forwardly, to assist in the complete separation of the sheet from the underlying ones and to break the adhesion caused by electrical attraction or the knitting togethe of the fibers of the sheet, especially at the sheared edges of the pile. This feature is particularly useful in handling thin tissues Or sheets of exceptionally large area.

The present invention also provides intermittently actuated stop means disposed in the vicinity of the friction buckling member for limiting the extent of the buckled portion of the sheet, and which may be employed as the sole sheet stopping means or may be used in conjunction with the intermittent front stop or guide described. Other novel features are provided in connection with the construction and operation of the buckling member itself and of the air blast device.

Further objects and features of novelty will also be apparent from the following specification when read inconnection with the accompanying drawings in which certain embodiments of the invention are illustrated by way of example,

In the drawings:

Figure 1 is a fragmentary plan View of a sheet feeder embodying the features of the invention;

Figure 2 is a vertical View in longitudinal section taken on line 2-2 of Figure 1;

Figure 3 is a similar view taken on line 3-3 of Figure 1, and on a slightly enlarged scale;

Figure 4 is a detail view in vertical section taken on line t'-4 of Figure l, and on a further enlarged scale;

Figure 5 is a similar view taken on line 55 of Figure 1 and showing one of the laterally spaced combing or buckling devices;

Figure, 6 is a view in horizontal section taken on line 6-43 of Figure 2 and showing some of the actuating mechanism for the feeder, this figure also incorporating an alternatively usable driving means for the air blast tube;

Figure 7 is a fragmentary view in vertical 1ongitudinal section taken substantially on line 1-1 of Figure 6, and illustrating in further detail the blast tube rotating gearing which features the modification shown in Figure 6; and

Figure 8 is a view in transverse horizontal cross section of a portion of the air blast and supporting tube, this view showing a modification applied to the device at the point designated VIII in Figure 1.

A feeder which embodies the principles of the present invention may be self-contained and supported upon its individual base or supporting frame and driven from its own source of power, or it may 'be incorporated in the machine to which the sheets are to be fed, for example, a printing press, folder, slitter, shear, or collating machine, and supported upon the framework of the latter mechanism. The lower portions of the feeding device are not involved in the present invention and are therefore not illustrated nor described. It is sufficient to state that th ile of sheets indicated at P are preferably supported upon a feed board of the usual automatic elevating type and disposed between the side frames and l l which extend upwardly from and form a part of the frame of the device.

Supported for fore and aft movement upon the side frames I0 and II is the feeder carriage which is indicated generally by the reference character A. This carriage comprises the combined bracket and gear box I2 upon one side of the apparatus and the sliding bracket l4 disposed at the opposite side. These two adjustable members are connected by the transverse cam and driving shaft I5 and the tubular cross shaft IS, the latter performing the dual function of furnishing the main support for the feeding and buckling units and providing the means for directing an air blast upon the pile to aid in the feeding of the sheets. Supported upon this tubular shaft l6 adjacent the central portion of the machine is the main feeding and buckling device designated generally by the reference character B, and similarly supported upon opposite sides of the main feeding device and directly above the rear corners of the pile are the separating buckler or. combing devices C, which serve to effect a. preliminary loosening or separation of the top sheets preparatory to their being moved forwardly from the pile.

The feeder carriage A is supported from the side frames I0 and II by means of the racks l8 and I9, the rack l8 being secured rigidly in spaced relation to the side frame ID by means of the studs 20, and the rack l9 being similarly secured by means of the studs 2| to the side frame II. The bracket and housing member I2 is slidably mounted upon the rack I8 by means of the plates 22 which embrace the rack l8, and the opposite bracket I4 is divided or slotted in a similar manner to embrace and ride upon the opposite rack l9. In order to effect the longitudinal adjustment of the carriage A upon the racks, there are provided the pinions 23 and 24 which are keyed to the transverse shaft 25 and suitably held by members l2 and I4 against transverse displacement. A hand wheel 26 is provided upon the end of the pinion shaft 25 by means of which movement of the carriage A may be accomplished.

As is usual in sheet feeders of this type, there is provided at the forward end of the device, a tape conveyor which comprises the tapes 3!! trained about the pulleys or rolls 3| carried by the'transversedrive shaft 32 which has bearing support adjacent its respective ends in the drive housing 34 and in the opposite side frame ll. As shown in Figure 3 of the drawings, top rolls 35 are provided above the conveyor rolls 3! and bearing upon the tapes 39 at the inlet end of the conveyor. Also at the front end of the pile P, there is preferably provided the intermittently movable front stop elements 38 carried by the transversely extending rock shaft 39 adjacent the end of which is fixed the cam actuated arm 40, which carries a roller 4! adapted to be contacted and moved by the cam 42 carried by the conveyor drive shaft 32. The rock shaft 39 may be urged in the counter-clockwise direction as viewed in Figure 3 by means of a spring 44 (shown in Figure 6) which may be secured to any fixed portion of the frame and connected to a vertical arm 45 carried by the shaft 39.

The conveyor drive shaft 32 not only provides the cam actuation of the front stops 38, but also transmits the driving force to the separating and feeding devices B and C as will be presently described. The shaft 32 which carries a gear 46, is itself driven by means of suitable gearing as suggested at 4'! in Figure 2, from a suitable source of power, preferably synchronized with the driving member to which the sheets are to be fed.

The main buckling feeder unit B, shown to best advantage in Figures 1, 3 and 4, comprises a bifurcated forwardly extending frame 55'], the arms of which are provided with openings which receive the tubular supporting shaft it. One of these arms has a vertical extension 5| which carries at its upper end a roller 52 which follows the cam 54 fixed to and rotatable with the cam and drive shaft l5. Transverse displacement of the forwardly extending frame 56 on the supporting tubular shaft I6 is prevented by the collars 56 which are provided at the remote sides of the frame. At points spaced apart at the forward end of the U-shaped frame 50, there are provided the two hold-down pads or fingers 58, which are carried by the lower ends of the pins 59 and urged toward the top of the pile by means of the springs 69. A vertical adjustment of the hold-down or stop pads 58 may be obtained by means of the nuts 62.

Between the bifurcations of the U-shaped frame 50, there is disposed a roller carrying arm 65. This arm is preferably made of tWo spaced plates 65 and 61 connected by a shaft 68 which carries the friction feeding wheel or roller 16. The supporting arm 65 is fulcrumed upon the tube It and its forwardly projecting end i2 is provided with a roller 13, which follows the cam 15 carried by the cam shaft i5. By this means the feeding roller H! may be raised from and lowered upon the top of the pile during the operation of the feeder. In order to drive the roller 10 in a direction to buckle and feed the sheets forwardly, a gear 1'! is fixed to the roller and meshes with another gear 78 carried by the tubular shaft l5 and this gear in turn meshes with the drive gear 79 carried by the shaft l5. The relation of these several gears is indicated by the arrows in Figure 4.

Embraced between the plate 57 of the wheel carrying arm 65 and one of the blades of the arm 50 is the hold-back or pressure finger 89 which is of an angular construction so that its rearward and downwardly projecting end 8| may bear upon the extreme rear margin of the top of the pile behind the feed roller 10, so as to prevent any forward movement of the underlying sheets when the top-sheet is buckled and fed toward the front of the pile.

The laterally disposed preliminary buckling or combing devices designated are of identical construction except that theyare reversedso as to operate at the opposite corners of the pile. Therefore, only one of these units need be described. For purposes of explanation, the one shown in the lower portion of Figure 1 and illustrated to the best advantage in Figure has been selected and particularly described. The buckling or combing unit C comprises an angular casting 85 which is provided with an opening to freely receive the supporting tube I 6. An intermediate diagonal portion of the bracket 85 provides bearings foran axle 85 upon one end of which is-mounted the combing or lateral buckling roller 88, and the other end of which carries a pinion 89 which meshes with a bevel gear 99 forming part of the double gear arrangement including the gear 9| which is supported upon the tubular shaft l6 and maintainedclosely adjacent the bracket 85. The gear 9| meshes with a gear 93 which is keyed to the cam and drive shaft l5. A forwardly extending end 94 of the bracket 85 carries a roller 95. which follows the cam 98 which is splined to theshaft l5 as at 91. An angular portion 98. of the bracket 85 carries the pressure finger I09 which is of the same construction and arrangement as the pad or finger 58 described in connection with the main feeding device B, being spring pressed andprovidedwith the knurled adjusting nut IOI. A rearward extension 192 of the bracket 85' carries the side pile gauge blade I103 and the rear pile gauge blade I94.

The transmission between the tape driving shaft 32 and the feeder driving andcam shaft will now be described. Within the gear housing 3 5, there is mountedupon suitable stub shafts, the spur gear 105 and'the doublespur and bevel gear unit 16. The gear I05 meshes with the gear 46 carried by the tape conveyor shaft 42 and also meshes with the spur portion I91. of the double gear I56, the bevel portion I08 of which is .1

arranged to mesh with the bevel gear I09 which is keyed to the longitudinally extending drive shaft I it. This drive shaft has bearings II I and H2 in the gear housing 34 and bearings I I3 and H4 in the housing bracket l2 of the feeder carriage A. Within the housing bracket 12, a bevel gear H5 is splined upon the longitudinal drive shaft H0 and meshes with a bevel gearl l6 carried upon one end of the cam and drive shaft [5 for the feeding and combing units.

The tubular shaft I6 is plugged at its both ends and is provided with the branch I29 to which is applied the flexible conduit [22 which may be connected either directly or through suitable valve devices to a source of compressed air. The tube It is provided with a series of openings I25 in the wall thereof through which jets of air I26 are directed downwardly and preferably forwardly upon the top sheets of the pile in order to aid the feeding operation as will be presently described. Certain modifications of the air tube arrangement are provided, the details of which may best be described in connection with the general operation of the device.

The operation of the improved sheet feeder will now be set forth. When the pile board is raised in order to bring the pile P to the proper height to initiate the feeding operation, the mechanism is started and the wheels 88 of the buckling or combing devices C upon either side of the rear portion of the pile, buckle the opposite corners of the top sheet S in a diagonally forward and inward direction toward the buckling stops or pressure pads Hill, the buckling wheels 88 having been previously moved downwardly into contact with the top of the pile by means of the cam follower arm 94 and the cam 96 carried by the shaft I5. These buckling or combing wheels serve to break the rear corners of the top sheet S loose from the pile.

Then substantially simultaneously with the raising of the combing devices C from the pile,

the main friction buckling feed roller 10 of the feeding device B is lowered into contact with the central rear portion of the top sheet S by means of the cam 15 and cam follower arm 12. The friction roller 10 is driven continuously through the chain of gearing I1, 18, and 19 and its sheet contacting surface is made of rubber, leather, or a similar substance, the friction between this surface and that of the top sheet being, of course, greater than the friction between the top sheet and the next underlying sheet. If desired, the surface of the roller 19 may be provided with a series of protuberances, or roughened in any desired way.

At this time also, the forwardly disposed pressure finger or pad 58 is brought into contact with the sheet S at a point spaced forwardly of the point of tangency of the roller H! by means of the cam 58 and cam follower 5|, 52. The rotation of the roller causes the sheet S to buckle against the pad 58 as clearly shown in Figures 3 and e. The finger 89, 8| remains in contact with the top surface of the rear margin of the pile at all times, and serves to retain the underlying sheets against movement while the sheet S is being buckled and fed forwardly. Next the buckler stop pads 58 are raised While at the'same time the front stops 33 (if such are employed) are swung out of the way by the operation of the cam 42. The feed roller I0 continues to rotate and the air blast 425 from the orifices I25 in the tube I5 assists in flattening the sheet out and moving the buckled portion toward the front of the pile so that the front edge of the sheet is fed into the bite of the conveyor 39 between the tapes and the top rollers 35, whereupon they are carried toward the point of delivery. The separating and feeding roller Y!) is raised as soon as the conveyor, 38 grips the front edge of the sheet. The rear combers C will again operate upon the next sheet as soon as the tail edge of the preceding sheet has passed the stop fingers or pads, and the central forwardly feeding device B will again operate to bring the feeding roller '58 down. upon the top of the next sheet.

It will be noted that by these operations the sheets are fed to the point of delivery in an overlapping manner, the distance between the front edges of successive sheets being approximately equal to that between the rear edge of the pile and the buckle stop fingers 58.

Several methods of utilizing the air blast in breaking the buckle and projecting the sheets forwardly of the pile may be employed. The air blast .tube l8 may be mounted rigidly in the bracket portions '5 Z and It with the blast directed toward the sheets, always at the same angle,

preferably as shown in Figure 4 of the drawings. In this case the blast may be either continuous or intermittent, an intermittent blast being preferred especially in thecase of thin sheets, so as not to tend to prevent the formation of the buckle. In a second mode of operation of the blast device, the greater portion of the tube I6 is rotatable, this rotation being effected by fixing the gear I8 or the gear 9| to the tubular shaft so that it will rotate therewith. Any suitable junction between the rotatable portion of the tube i6 and the stationary portion I (shown in Figure 8 of the drawings), which is provided with the nipple I to which the flexible tube I2I is connected, may be provided. As suggested in Figure 8, the stationary portion of the tube is arranged to telescope within the end of the rotatable portion i6, relative longitudinal movement being prevented by the collar I fixed to the portion Hi. In this way the blast tube IE would be given a clockwise rotation as viewed in Figures 3 or 4 of the drawings and the blast would move from front to rear in its impingement upon the sheets. This arrangement is not as preferable as one in which the tube I6 would rotate in a counter-clockwise direction and thus give a forward brushing movement along the buckled portion of the sheet. This rotation of the tube It may be readily effected by the insertion of an additional idler gear between the tube I6 and the drive shaft I5. is suggested in Figures 6 and 7 of the drawings in which a gear If!) is secured to the shaft I 5 closely adjacent the housing bracket I2. A similar gear MI is fixed to the tube I6 in co-planar relation to the gear MI! and an idler I42 is carried by the stub shaft I43 supported on the bracket or housing I2 and meshes with both of the gears Mi] and MI.

Various changes and modifications may be made in the embodiment of the invention illustrated and described herein without departing from the scope of the invention as determined by the following claims,

Having thus described the invention, what is claimed as new and desired to be secured by Letters Patent is:

1. A sheet feeder of the stream feeding type which comprises means for supporting a pile or bank of superposed sheets and means for effecting the feeding of successive top sheets from the pile in overlapping relation, said latter means comprising stop means for forward portions of a top sheet, means for forming a buckle in said sheet in a fore and aft direction, said stop means disposed to contact the sheet intermediate the length of the latter at a point spaced from the front edge of the sheet, means for releasing said stop means to allow the buckled portion of the sheet to straighten out and the front edge to project forwardly of the pile, and means for timing the actuation of the buckling means to operate upon the next succeeding sheet before the preceding sheet has cleared the pile.

2. A sheet feeder of the stream feeding type which comprises means for supporting a pile or bank of superposed sheets and means for effecting the feeding of successive top sheets from the pile in overlapping relation, said latter means comprising stop means for forward portions of a top sheet and a rotary member having a friction surface, means for continuously rotating said member while in contact with the successive top sheets of the pile in order to form a buckle in said sheet in a fore and aft direction, said stop means disposed to contact the sheet intermediate the length of the latter at a point spaced from the front edge of the sheet, means for releasing said stop means to allow the buckled portion of the sheet to straighten out and the front edge to project forwardly of the pile, and means Such an arrangement l for timing the actuation of the buckling and stop means to operate upon the next succeeding sheet before the preceding sheet has cleared the pile.

3. A sheet feeder of the stream feeding type which comprises means for supporting a pile or bank of superposed sheets, a sheet forwarding means arranged in advance of the front edge of the pile, a frictional feeding element for contacting the successive top sheets of the pile at a point adjacent the rear edge and moving said sheets off of the pile and onto said forwarding means in overlapping relation, laterally disposed friction combing devices adapted to effect a preliminary separation of the sheets from the rear portion of the pile, and means for timing the actuation of said frictional element and said combing devices to operate upon the next succeeding sheet before the preceding sheet has cleared the pile.

4. A sheet feeder which comprises means for supporting a pile or bank of superposed sheets and means for efiecting the feeding of successive top sheets from the pile, said latter means comprising stop means for forward portions of a top sheet, means for forming a buckle in said sheet in a fore and aft direction, means for releasing said stop means, means for substantially simultaneously delivering a blast of air downwardly upon the buckled portion of the sheet to cause it to straighten out and the front edge thereof to project forwardly of the pile, and means for rotating said blast delivering means So as to bring the blast of air intermittently into contact with said sheet.

5. A sheet feeder which comprises means for supporting a pile or bank of superposed sheets and means for effecting the feeding of successive top sheets from the pile, said latter means comprising stop means for forward portions of a top sheet, means for forming a buckle in said sheet in a fore and aft direction, means for releasing said stop means, and means for substantially simultaneousl delivering a blast of air downwardly upon the buckled portion of the sheet to cause it to straighten out and the front edge thereof to project forwardly of the pile, and means for rotating said blast delivering means in a vertical longitudinal plane and in a direction to cause the blast to contact said sheet successively from rear to front, whereby a forward brushing effect on the buckled sheet is attained.

6. A sheet feeder which comprises means for supporting a pile or bank of superposed sheets and means for effecting the feeding of successive top sheets from the pile, said latter means comprising a stop element adapted to prevent movement of a relatively forward portion of the top sheet, friction means for buckling the top sheet forwardly against said stop element, means for intermittently alternately actuating and releasing said stop element, a rotary air blast member having an orifice for delivering a jet of air radially thereof, said member being disposed above the portion of the pile where the sheets are buckled, and means for rotating said member to wipe the jet of air along the succcessive buckled sheets upon each release of said stop member, in order to assist in straightening out the sheets and projecting the forward edges from the pile.

7. A sheet feeder which comprises means for supporting a pile or bank of superposed sheets and means for effecting the feeding of successive top sheets from the pile, said latter means comprising a stop element adapted to prevent movement of a relatively forward portion of the top sheet, a friction feedwheel for buckling the-top sheet forwardly against said stopelement, means for continually rotating said wheel, means for intermittently alternately actuating and releasing said stop element, a rotary air blast member having an orifice for delivering a jet of air radially thereof, said member being disposed above the portion of the pile where the sheets are buckled, and means for rotating said member friction feed device and a sheet stop element,

both carried by said feed bracket and disposed in alignment longitudinally of the pile, means for substantially simultaneously bringing the feed device and the stop element down upon the top of the pile, means for actuating said friction feed device, whereby the top sheet of the pile is,

buckled forwardly against said stop, means for raising the stop element to permit the buckle to move forwardly therebeneath and'project the forward edge of the sheet from the pile, and means for thereafter raising the friction feeding device from the pile.

9. A sheet feeder which comprises means for supporting a pile or bank of superposed sheets and means for effecting the feeding of successive top sheets from the pile, said latter means com prising a feed bracket disposed above the pile, a friction feed wheel and a sheet stop pressure finger both carried by said feed bracket and dis-.

posed in alignment longitudinally of the pile, means for substantially simultaneously bringing the feed wheel and the stop finger down upon the top of the pile, means for continually rotating said friction feed wheel in the forward feeding direction, whereby the top sheet of the pile is buckled forwardly against said stop, means for raising the stop finger to permit the buckle to move forwardly therebeneath and project the forward edge of the sheet from the pile, and means for thereafter raising the friction feeding wheel from the pile.

10. A sheet feeder which comprises means for supporting a pile or bank of superposed sheets and means for effecting the feeding of successive top sheets from the pile, said latter means comprising a feed bracket disposed above the pile, a friction feed device and a sheet stop element both carried by said feed bracket and a common fulcrum axle for said device and element on said bracket and arranged so that these parts are disposedin alignment longitudinally of the pile, synchronized cam means on said bracket adjacent said fulcrum axle, means for substantially simultaneously bringing the feed device and the stop element down upon the top of the pile, means for actuating said friction feed device, whereby the top sheet of the pile is buckled forwardly against said stop, means for raising the stop element to permit the buckle to move forwardly therebeneath and project the forward edge of the sheet from the pile, and means for thereafter raising the friction feeding device from the pile.

11. A sheet feeder which comprises means for supporting a pile or bank of superposed sheets and means for effecting the feeding of successive top sheetsfrom the pile, said latter means comprising a feeding head disposed above the pile, a-

transverse supporting shaft on said head and a rotary'driven shaft on said head and disposed parallelwith said, supporting shaft, a swinging frame pivotally mounted on said supporting shaft,

a friction feedingwheel journalled in said frame,

another frame fulcrumed on said supporting shaft, a stop finger on said latter pivoted frame and adapted to bear on the top of the pile in advance of the feedingwheel, cams on said rotary driven shaft for swinging said frames in timed sequence to causethe friction feed Wheel to intermittently buckle the successivetop sheets against the stop finger, release the finger to permit the sheet to project forwardly as the buckle straight- Y ens, and finally toraise the feed wheel.

12. A sheet feed-er which comprises means for supportinga pile or bank of superposed sheets and means for eifecting the feeding of successive top sheets from the pile, said latter, means comprising a feeding head disposed above the pile, a transverse supporting shaft on said head and a rotary drivenshaft on said head and disposed parallel with said'supporting shaft, a swinging frame pivotally mounted on said supporting shaft, a friction feeding wheel journalled in said frame, another. frame fulcrumed on said,

supporting shaft, a stop finger on said latter pivoted frame and adapted to bear on the top of i the pile in advance of the feeding wheel, and cams on said rotary driven shaft for swinging said frames in timed sequence to cause the friction feed wheel to intermittently buckle the successive top sheets against the stop finger, release the finger to permit the sheet to project for- 'wardly as the-buckle straightens, and finally to raise the feed wheel, said supporting shaft being hollow, connected with a source of compressed air, and provided with radial orifices for the projection of jets of air upon the buckled sheetto aid in straightening out the sheet and projecting it forwardly.

13. A sheet feeder which comprises means for supporting a pile or bank of superposed sheets and means for effecting the feeding of successive top sheets from the pile, said latter means compris ing a feeding head disposed above the pile, a transverse supporting shaft on said head and a rotary driven shaft on said head and disposed parallel with said supporting shaft, a swinging frame pivotally mounted on said supporting shaft, a friction feeding wheel journalled in said frame, another frame fulcrumed on said supporting shaft, a stop finger on said latter pivoted frame and adapted to bear on the top of the pile in advance of the feeding wheel, cams on said rotary driven shaft for swinging said frames in, timed sequence to cause the friction feed wheel: to intermittently buckle the successive top sheets.

against the stop finger, release the finger topermit the sheet to project forwardly asthe bucklei straightens, and finally to raise the feed wheel,

said supporting shaft being hollow, connected, with a source of compressed air, and provided with radial orifices for the projection of jets of: air upon the buckled sheet to aid in straighten-,

ing out the sheet and projecting it forwardly, and means for rotating said hollowsupporting shaft to intermittently bring the jets into impingement upon the buckled sheet.

14. A sheet feeder which comprises means for supporting a-pile or bank of superposed sheetsand means-foreffecting the feeding of successive top sheetsfrom the pile, said latter means comprising a feedinghead disposed above the pile, a transverse supporting shaft on said head.

and a rotary driven shaft on said head and disposed parallel with said supporting shaft, a swinging frame pivotally mounted on said supporting shaft, a friction feeding wheel journalled in said frame, another frame fulcrum-ed on said supporting shaft, a stop finger on said latter pivoted frame and adapted to bear on the top of the pile in advance of the feeding wheel, cams on said rotary driven shaft for swinging said frames in timed sequence to cause the friction feed wheel to intermittently buckle the successive top sheets against the stop finger, release the finger to permit the sheet to project forwardly as the buckle straightens, and finally to raise the feed wheel, said supporting shaft being hollow, connected with a source of compressed air, and provided with radial orifices for the projection of jets of air upon the buckled sheet to aid in straightening out the sheet and projecting it forwardly, and means for rotating said hollow supporting shaft in a direction to intermittently bring the jets into impingement upon the buckled sheet with a brushing movement in a forward direction.

15. A sheet feeder which comprises means for supporting a pile or bank of superposed sheets and means for effecting the feeding of successive top sheets from the pile, said latter means comprising a feeding head disposed above the pile, means for adjusting said head in'a fore and aft direction to adapt the feeder to sheets of various lengths, a friction feeding device carried by said head at a point intermediate the width thereof, and a friction device for buckling the sheets transversely inwardly of the pile, carried by said head adjacent each of the side portions thereof.

16. A sheet feeder which comprises means for supporting a pile or bank of superposed sheets and means for effecting the feeding of successive top sheets from the pile, said latter means comprising a feeding head disposed above the pile, means for adjusting said head in a fore and aft direction to adapt the feeder to sheets of various lengths, a friction feeding device carried by said head at a point intermediate the width thereof, a friction device for buckling the sheets transversely inwardly of the pile, carried by said head adjacent each of the side portions thereof, and a common driving means for said feeding and buckling devices also carried by said adjustable head.

17. A sheet feeder which comprises means for supporting a pile or bank of superposed sheets and means for effecting the feeding of successive top sheets from the pile, said latter means comprising a feeding head disposed above the pile, a transverse supporting shaft on said head and a rotary driven shaft on said head and disposed parallel with said supporting shaft, both shafts extending substantially the full width of the pile, a sheet feeding device carried by said head at a point intermediate the width thereof and comprising a swinging frame pivotally mounted on said supporting shaft, a friction feeding wheel journalled in said frame, another frame fulcrumed on said supporting shaft, a stop finger on said latter pivoted frame and adapted to bear on the top of the pile in advance of the feeding wheel, cams on said rotary driven shaft for swinging said frames in timed sequence, a friction device for buckling the sheets transversely inwardly of the pile carried by said head adjacent each of the side portions thereof, each of said last named devices comprising a pivoted frame fulcrumed on said supporting shaft and carrying a buckling wheel and a buckle stop finger aligned laterally of the pile, a cam on said rotary driven shaft for intermittently raising and lowering said last named frame to bring the buckling wheel and finger into contact with the pile in timed sequence with the parts of the intermediate feeding device.

18. A sheet feeder which comprises means for supporting a pile or bank of superposed sheets and means for effecting the feeding of successive top sheets from the pile, said latter means comprising a feeding head disposed above the pile, a transverse supporting shaft on said head and a rotary driven shaft on said head and disposed parallel with said supporting shaft, both shafts extending substantially the full width of the pile, a sheet feeding device carried by said head at a point intermediate the width thereof and comprising a swinging frame pivotally mounted on said supporting shaft, a friction feeding wheel journalled in said frame, another frame fulcrumed on said supporting shaft, a stop finger on said latter pivoted frame and adapted to bear on the top of the pile in advance of the feeding wheel, cams on said rotary driven shaft for swinging said frames in timed sequence, a friction device for buckling the sheets transversely inwardly of the pile carried by said head adjacent each of the side portions thereof, each of said last named devices comprising a pivoted frame fulcrumed on said supporting shaft and carrying a buckling wheel and a buckle stop finger aligned laterally of the pile, a cam on said rotary driven shaft for intermittently raising and lowering said last named frame to bring the buckling wheel and finger into contact with the pile in timed sequence with the parts of the intermediate feeding device, and gearing carried by said rotary shaft and said frames for rotating said several wheels, said supporting shaft being hollow, connected with a source of compressed air, and provided with radial orifices for the projection of jets of air upon the buckled sheet to aid in straightening out the sheet and projecting it forwardly.

19. A sheet feeder of the stream feeding type which comprises means for supporting a pile or bank of superposed sheets and means for effecting the feeding of successive top sheets from the pile in overlapping relation, said latter means comprising a feed bracket disposed above the pile, a friction feed device and a sheet stop element both carried by said feed bracket and disposed in alignment longitudinally of the pile, means for substantially simultaneously bringing the feed device and the stop element down upon the top of the pile, means for actuating said friction feed device, whereby the top sheet of the pile is buckled forwardly against said stop, means for raising the stop element to permit the buckle to move forwardly therebeneath and project the forward edge of the sheet from the pile, and means for thereafter raising the friction feeding device from the pile, and means for timing the repeated cycles of operation so that the feeding device is set down upon the pile immediately the tail end of a preceding sheet has cleared the stop element, whereby the amount of overlap of the sheets is equal to the distance from the rear edge of the pile to the stop element.

20. A sheet feeder of the stream feeding type which comprises means for supporting a pile or bank of superposed sheets and means for effecting the feeding of successive top sheets from the pile in overlapping relation, said latter means comprising stop means for forward portions of a top sheet, said stop means disposed to contact the sheet intermediate the length of the latter at a point spaced from the front edge of the sheet, a pressure means adapted to maintain continuous contact with the rearmost portion of the top sheet, means located between said stop and pressure means adapted to withdraw said rearmost portion of the top sheet from under said pressure means and to buckle said top sheet 10 in a fore and aft direction against said stop means, means for releasing said stop means to allow the buckled portion of the sheet to straighten out and the front edge to project forwardly of the pile, and means for timing the actuating of the buckling means to operate upon the next succeeding sheet before the preceding sheet has cleared the pile.

THEO. J. KAUFFELD. 

